refactor: moved Vec impl Cow into cow.rs

library/alloc/src/vec/cow.rs

@@ -0,0 +1,35 @@
+use crate::borrow::Cow;
+use core::iter::{FromIterator};
+
+use super::{Vec};
+
+#[stable(feature = "cow_from_vec", since = "1.8.0")]
+impl<'a, T: Clone> From<&'a [T]> for Cow<'a, [T]> {
+    fn from(s: &'a [T]) -> Cow<'a, [T]> {
+        Cow::Borrowed(s)
+    }
+}
+
+#[stable(feature = "cow_from_vec", since = "1.8.0")]
+impl<'a, T: Clone> From<Vec<T>> for Cow<'a, [T]> {
+    fn from(v: Vec<T>) -> Cow<'a, [T]> {
+        Cow::Owned(v)
+    }
+}
+
+#[stable(feature = "cow_from_vec_ref", since = "1.28.0")]
+impl<'a, T: Clone> From<&'a Vec<T>> for Cow<'a, [T]> {
+    fn from(v: &'a Vec<T>) -> Cow<'a, [T]> {
+        Cow::Borrowed(v.as_slice())
+    }
+}
+
+#[stable(feature = "rust1", since = "1.0.0")]
+impl<'a, T> FromIterator<T> for Cow<'a, [T]>
+    where
+        T: Clone,
+{
+    fn from_iter<I: IntoIterator<Item = T>>(it: I) -> Cow<'a, [T]> {
+        Cow::Owned(FromIterator::from_iter(it))
+    }
+}

library/alloc/src/vec/mod.rs

@@ -89,6 +89,8 @@ pub use self::drain::Drain;
 
 mod drain;
 
+mod cow;
+
 /// A contiguous growable array type, written `Vec<T>` but pronounced 'vector'.
 ///
 /// # Examples
@@ -3013,41 +3015,6 @@ impl<T, A: Allocator, const N: usize> TryFrom<Vec<T, A>> for [T; N] {
     }
 }
 
-////////////////////////////////////////////////////////////////////////////////
-// Clone-on-write
-////////////////////////////////////////////////////////////////////////////////
-
-#[stable(feature = "cow_from_vec", since = "1.8.0")]
-impl<'a, T: Clone> From<&'a [T]> for Cow<'a, [T]> {
-    fn from(s: &'a [T]) -> Cow<'a, [T]> {
-        Cow::Borrowed(s)
-    }
-}
-
-#[stable(feature = "cow_from_vec", since = "1.8.0")]
-impl<'a, T: Clone> From<Vec<T>> for Cow<'a, [T]> {
-    fn from(v: Vec<T>) -> Cow<'a, [T]> {
-        Cow::Owned(v)
-    }
-}
-
-#[stable(feature = "cow_from_vec_ref", since = "1.28.0")]
-impl<'a, T: Clone> From<&'a Vec<T>> for Cow<'a, [T]> {
-    fn from(v: &'a Vec<T>) -> Cow<'a, [T]> {
-        Cow::Borrowed(v.as_slice())
-    }
-}
-
-#[stable(feature = "rust1", since = "1.0.0")]
-impl<'a, T> FromIterator<T> for Cow<'a, [T]>
-where
-    T: Clone,
-{
-    fn from_iter<I: IntoIterator<Item = T>>(it: I) -> Cow<'a, [T]> {
-        Cow::Owned(FromIterator::from_iter(it))
-    }
-}
-
 ////////////////////////////////////////////////////////////////////////////////
 // Iterators
 ////////////////////////////////////////////////////////////////////////////////